speaker noise

Comparison of Beverage antenna - A ranking of receiving antennas based on noise being evenly distributed in all directions. These rankings are most accurate in the frequency range of AM broadcast, 160 or 80 meter bands

A Horn Antenna for 2.4 GHz. - This Antenna is not really practical for AO-40 reception, but horn antennas have a number of qualities useful in microwave antenna testing and noise figure measurements.

Interference Cancelling System - The use of interference signal cancellation has been around for some time. The idea is to use an auxiliary antenna almost any random length of wire in addition to the main receiving antenna

BHI - Speakers and RFI noise reduction products

BHI Ltd - Noise eliminating products. Remove unwanted background noise and interference leaving only the speech. Clear communications, listen stress free. Dsp noise cancellation solutions.

Tennamast - Tennamast design and manufacture a wide range of fabricated metal goods, Antenna masts, Wind-sock masts, and masts for holding such systems as CCTV, Loudspeakers, Lighting units

Sounds Sweet Communications Speakers - Speakers for Amateur Radio, 2-Way Radio, Shortwave and Scanner listening

Psk31 - PSK31 is a digital communications mode which is intended for live keyboard-to-keyboard conversations, similar to radioteletype. Its data rate is 31.25 bauds (about 50 word-per-minute), and its narrow bandwidth (approximately 60 Hz at -26 dB) reduces its susceptibility to noise.

Antenna Noise and Signal Cancelling at LF - The fact that the phasing between a wanted signal and an unwanted signal can be different on different antennas is put to advantage. With this condition, the unwanted signal can be cancelled out by controlling amplitude and phase. The heart of the system is some form of phase control circuitry.

KØBG's ham radio mobile operator web site - This site is dedicated to mobile amateur radio operators, old and new alike. Whether you are into HF, or VHF operation, I trust the information presented will increase your enjoyment of our great hobby. With safety as a byword, there are articles on amplifiers, antennas, bonding, impedance matching, installing hardware, mobile equipment, noise and RFI abatement, wiring, and much more. I do my best to keep these articles up to date, and easy to follow.

Mods fro Yaesu FT-1000 (FT 1000 FT1000) - ham.dmz.ro FT1000 pages

FT817 DSP noise reduction noise - Add-on audio DSP unit from BHI

FT-897 noise blanker - KR1ST, Yaesu FT-897 Noise blanker review

Less White Noise - FT-897D Modification - Modification for FT-879D to remove the white noise spreaded far above 3 kHz by Petr OK1FIG

Bob-and-Linda Amateur Radio Catalog - Antennas, books, cables and connectors, mounts, speakers

DSPBOX - DOS Freeware, DSPBOX is an attempt to code the Texas Instruments DSK 'C50 in such a way to make it behave like a commercial DSP noise reduction unit, like the NIR-12, the TimeWave 599+ and others. Not only the noise reduction function has been implemented, but automatic notch, AGC and Band Pass have as well.

WD6CNF DSP Filter - Audio Digital Filter, two bandpass filters, three notch filters, two noise filters graphical setting of filter center frequency and bandwidth Drag vertical lines on top of signal, Microphone input, speaker output Mono, 5 kHz bandwidth

WD6CNF Voice keyer - Audio voice keyer Microphone input, speaker output Live microphone enable Record/play audio from twelve memories Display text of recorded audio Transmitter keyed via serial (com) port Loop (with variable delay) audio output

HamView - A freeware program to dig out weak signals buried in noise, functionally similar to the excellent FFTDSP of AF9Y, but with the added bonus of real time audio filtering of the incoming signals. Just point and click with the mouse, and the selected signal will stand out from the QRM and noise.

A cheap noise reducing speaker - Noise Reduction on the Cheap PDF File

QRM and noise reduction Priority listing - You will find on these pages my experiences and results on antennas and local/non-local QRM/noise reduction. Using a broadband vertical active magnetic loop and a home made / designed broadband amplifier. Two vertical magnetic Alford loops are used in an array. Analog and Digital Signal Processing and a dual phase coherent Software Defined Radio (SDR) are used. By PA0SIM

Common-Mode Noise - Receiving Common Mode Noise shows how lack of a balun can contribute to system noise

Automotive RFI elimination - ARRL pdf file on how remove car noise from your radio. Modern vehicles are RF noisy environments. Come learn how to identify and silence yor mobile noise sources, by WA6PDP

ARRLWeb: Solving Ignition Noise RFI - Solving Ignition Noise RFI article. Help on removing noise interfences caused by ignition

Alternators & Batteries - Influence of batteries on RFI and noise generation by k0bg